Tube lock for guns



W. SUMMERBELL Jan. 30, 1951 TUBE LOCK FOR GUNS 3 Sheets-Sheet 1 Filed Feb. 12, 1947 T05: 705! M/varm mlvucm-for, William E ummerh E11 Jan. 30, 1951 W. SUMMERBELL TUBE LOCK FOR GUNS Filed Feb. 12, 1947 s Sheet s-Sheet 2 :Fg a. J7

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TUBE LOCK FOR GUNS Filed Feb. 12, 1947 3 Sheets-Sheet 3 William Eummavhall Patented Jan. 30, 1951 TNT OFFICE TUBE LOCK FOR GUNS William Summerbell, Washington, D. 0.; Edith May Summerbell executrix of said William Summerbell, deceased Application February 12, 1947, Serial No. 727,984

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3'70 0. G. 757) Claims.

facilitate removal of the tube or barrel of a large caliber gun in the field'and allow SllbStltlltlOllof another barrel without having to transport the entire gun to some distant point.

While the invention is adaptable to various rangement and combination of parts involved types of guns, it is, in'the present instance, ap-

plied to the 90 mm. gun but it may readily be applied to guns of larger or smaller caliber. It is a particular aim of the invention to embody such a device in a simple and compact form, making it exceptionally important for use on guns of larger caliber. Likewise, it is sought to simplify and make more rapid the assembly and disassembly of the barrel and breech ring.

The breech end of a gun tube is segmentthreaded for'attachment to the breech ring which is screwed on the end of the tube. At present, the tube and breech ring are locked together at the top by a tube locking key which is secured in place by means of screws, a stop and a spring mounted above the key, and both a screw driver and a wrench are required to raise the key so that the barrel may be unscrewed and withdrawn from its engagement with the breech ring. These locking means, however, are not easily accessible unless other parts of the gun mounted above the breech are first removed.

In my invention the presently used means for securing the locking key are eliminated, and the locking key or barrel lock is secured and controlled from the open breech ring by simple and easily accessible means mounted on the said breech ring.

In order to avoid injury to personnel and damage to the gun, great caution is necessary in disassembling a gun tube from a breech ring since the tube must be turned exactly A of its circumferencet'o permit the interrupted threads of the bayonet joint to pass each other. Clearing of the threads is made certain in my invention by means which limit rotation of the tube, as will be hereinafter described and pointed out.

Another object of my invention is its effect in reducing the torque of the gun without the necessity of employing bolts or other restraining means.

Additional objects, advantages and features of the invention reside in the construction, ar-

in the embodiment of the invention, as will'be understood from the following description and accompanying drawings, forming part of the specification, wherein similar numbers are used to designate like parts throughout the specification and drawings.

In the drawings:

Figure 1 is a perspective view of thebreech. ring and tube assembly of a gun, showing the: location of the locking mechanism,

Figure 2 is a longitudinal section through the breech ring, taken on the line 22 of Figure 1,.

Figure 3 is a transverse section through the: barrell lock and gun tube facing the breech end; of the gun, taken on the line 3- 3 of Figure 2,, 1 lggure 4 is a perspective view of the barrel.

Figure 5 is a section taken on the line 5-5 of. Figure 2,

. Figure 6 is an elevation to an enlarged scale of the cam shaft,

Figure '7 is an elevation of the face of the cam shaft adjacent the breech ring,

Figure 8 is a transverse section through the cam shaft; taken on the line 88 of Figure 6,

Figure 9 is an elevation of the face of the cam shaft adjacent the barrel lock,

Figure 10 shows the indexing means on the rear face of the breech ring and on the face of the cam shaft as they appear within the rearward opening of the breech ring.

Figure 11 is an exploded perspective view of the segment-threaded connection between the breech block and the tube as well as the recesses in the tube by which it is limited in rotation within the breech ring and locked therein in firing position, and, Figs. 12 and 13 are sectional detail views taken in planes identified by lines |2-l2 and !3|3, respectively, of Fig. 11.

The numeral It shows a well known form of a breech ring as presently used on a mm. gun. into which the barrel or tube II of the gun is fitted, the rear portion of the said breech ring beinggenerally rectangular. The breech block has been omitted since its details are well known and form no part of the invention.

The breech end of the tube I l is provided with interrupted threads 12 which engage similar threads 12a in the interior of the breech ring I!) in a conventional manner. The said breech ring III is locked to the tube I! by means of a lock shaft l3 slidably mounted in a vertical bore [4 in the said breech ring In near its forward or muzzle end. The said lock I3 is formed with a foot I5, Fig. 4, functioning as a key to engage within a recess l6 in the tube See Fig. 11. A recess I! having the same width as the foot I5 is provided in the breech ring In, to open through the bore therein and the muzzle face of the breech ring to accommodate the foot when it is in a raised position during the removal and insertion of the tube A circumferential groove I8 equal in length to the circumferential extent of threads l2 and |2a, or one eighth of the circumference of the tube, and of approximately one-half the depth of the recess I6, is provided in the surface of the tube immediately adjoining and forming a continuation of recess I6 to define the limit of rotation of the tube II when the said segment threads are being disengaged in disassembly.

The breech ring In is bored and counterbored longitudinally to provide a bore I9 having s"ucessive portions of different diameters and extending from its rearward or breech face 20 to :and opening into the vertical bore I4, the axes 'of the said bores l4 and I9 being at right angles to each other. Another vertical bore 2| is pro vided in the said breech ring adjacent its rearward face 20, perpendicular to and communicating with the bore IS.

A cylindrical cam shaft 22 is rotatably mounted in the bore IS. The said shaft is formed with two annular flanges 23 and 24 at one end to have a smooth fit within the largest diametered portion of the bore l9 adjacent the rearward face 20. The annular groove 25, defined by and lying between flanges 23 and 24, is provided with a plurality of cylindrical recesses or pockets 26, 21, and 28, Fig. 8, of the same diameter as the bore 2|. In assembly of the shaft 22 Within the bore l9, these pockets 26, 21 and 28 will lie successively in the longitudinal or fore and aft plane of the bore 2| during rotation of the said shaft 22, and become in effect a continuation of the said bore 2|. The diameter of the body of the shaft 22 is increased immediately adjacent the shoulder 24 and again at its forward end to pro-' vide bearing surfaces for the shaft within the bore I9. A cylindrical eccentric trunnion or cam 29 is formed on the end of the shaft 22 farthest removed from the shoulders 23 and 24 to engage within a notch or groove 30 in the lock l3.

The face 3| of the shaft 22 adjacent the shoulder 23 is provided with three radial screw-driver slots 32, 33 and 34 of a depth greater than the width of the shoulder 23 whereby a screw driver blade may be inserted to lift a plunger '35 mounted in the bore 2|, the said plunger being urged downwardly by a spring 36 and re tained in the bore 2| by a plug 31, and dimensioned to fit slidably between the shoulders 23 :and 24 of the shaft 22.

The rear face 20 of the breech ring In is suitably engraved upon its surface in such manner that the position of the lock foot l will be indicated by an index 38 engraved on the face 3| of the shaft 22, as shown in Figure 10.

Thetube II is locked to the breech ring :0 by engagement of foot I 5 within recess I6. When shaft 22 has been rotated to move foot |5 to this position, index 38 points to the inscription Tube Locked. Plunger 35 is then located in pocket 26' and releasably held therein by spring 36. To remove the barrel or tube II from the breech ring ID a screw driver is inserted in the slot 32 and pressed against the bottom of the plunger 35, forcing it upward within the bore 2| against the resistance of the spring 36 until the said plunger has been released from its engagement within the pocket 26. The shaft 22 is then revolved in a counterclockwise direction by means of the screw driver until the arrow 38 points to the inscription Tube Unlocked, indicating that foot l5 has been lifted until its bottom surface is a little above the bottom of the recess or channel l8 to permit rotation of the tube through 45 and thereby separate the threads of the tube and breech ring. The pocket 21 is now in alignment with the bore 2| and the plunger 35 being released from the pressure of the annular groove 25 moves into the pocket 21 under the action of spring 36.

After shaft 22 is rotated to its Tube Unlocked" position, as just described, tube may be un screwed to disengage the interrupted threads of the tube and breech. The extent of this rotation is precisely determined and limited by engagenient between foot l5 and the end wall 39 of recess I8. Thus when rotation of the tube is stopped as just described it is known that the interrupted threads are entirely disengaged. However, the tube cannot be axially Withdrawn at this time because the bottom of foot l5, has only a small clearance radially outwardly of the bottom of recess |8.

The screw driver is now inserted in slot 33 and the plunger 35 is again forced up into the bore 2 I. The shaft 22 is again revolved counterclockwise until the arrow 38 points to the Tube Removed inscription whereupon the said plunger drops into the pocket 28, all in the manner heretofore described. Revolving the shaft 22 has caused the foot l5 to be lifted clear of groove l8, shoulder 39 and threads l2. The tube II is now free for axial withdrawal from the breech ring.-

To assemble a new tube, the indicating arrow will point to the inscription Tube Removed, and the tube is inserted into the breech ring in the usual manner. Thereupon, all of the heretofore described movements will be repeated but in reverse order, the shaft being revolved clockwise, until, upon completion of the operation, the arrow will point to the Tube Locked inscrip-- tion, indicating that the foot H3 is securely engaged within the recess it of the tube H. In this operation, when the index 38 is moved to Tube Unlocked position wherein foot |5 is just a little above or radially outwardly of the bottom of recess l8, rotation of the tube to a position wherein the interrupted threads are fully engaged, is determined when foot l5 abuts against the end of recess IS. The foot may then be moved into the recess, by operation of index 38 to Tube Locked position to posi tive'ly prevent all rotation of the tube relatively to the breech block.

It is to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention or thescope of the subjoined claims.

Having thus described my invention, I claim: 1 The combination with a gun tube and separable breech ring therefor, a cam shaft revolvably mounted within said breech ring, said cam shaft being provided with camming means at one end and two annular shoulders at the opposite end, a lock shaft provided with a foot to engage and lock said guntube to said ring and a recess to engage the camming means of the said cam shaft whereby said foot is freed from its locking en gagement with the gun tube when said cam shaft is rotated, plunger means cooperating with circumferentially spaced recesses in said cam shaft between said shoulders whereby said cam shaft may be held in a plurality of rotative positions, and indexing means between said ring and cam shaft to indicate said positions.

2. The combination recited in claim 1, there being a plurality of radial slots in the end of said cam shaft each said slot having a depth greater than the thickness of the adjacent shoulder whereby each slot opens into a respective one of said spaced recesses and whereby a bladed tool may be inserted into any slot aligned with said detent means to release the detent means from a recess and thereafter turn said cam shaft to a new determinable position.

3. In a device for looking a gun tube Within its breech ring, said tube having interrupted threads on its breech portion arranged to engage with a correspondingly threaded bore in said ring when said tube is inserted axially into said bore in a first position and rotated through a predetermined angle to a second position, a lock shaft fitting a radial bore in said ring and slida ble therein, said lock shaft having a foot on its inner end arranged to enter a recess in said tube when said tube is in said second position only, to thereby lock said tube against rotation, there being a circumferential groove in the ex terior surface of said tube, opening at one end into said recess and of less depth than said recess, said groove extending through said predetermined angle, a cam shaft journaled in said ring and having an eccentric portion engaging said shaft to move the same radially as said shaft is turned, and means to positively position said cam shaft to locate said foot at the level of the bottom of said groove, said eccentric portion comprising an eccentric pin on the end of said cam shaft and engaged with a transverse notch in said lock shaft, whereby rotation of said cam shaft positively moves said lock shaft radially in its bore, and detent means associated with said cam shaft to yieldingly position said shaft in a selected one of three rotative positions corresponding to positions of said foot (1) in said recess, (2) at the level of the bottom of said groove and (3) at the level of the exterior surface of said tube.

4. In a gun tube positioning and locking mechanism for a gun having a tube and breech ring separable by limited rotation of said tube from a second to a first position, followed by axial withdrawal from said ring, locking means carried by said ring for movement radially of said tube from a first adjustment free of said tube to successive second and third adjustments radially inwardly of said first adjustment, means fixed with said tube and cooperating with said looking means when the latter is in said second adjustment, to limit rotation of said tube between first and second positions, and means fixed with said tube and cooperating with said locking means only when said locking means is in third adjustment to positively lock said tube in said second position, adjusting means carried by said ring and operable to selectively move said looking means to first, second and third adjustment, and securing means carried by said ring to releasably hold said locking means in selected adjustment.

5. A mechanism as in claim 4, said adjusting means comprising a shaft journaled in said ring and having three positions of rotational adjustment and having one end exposed, there being flats on said one end corresponding to said three adjustment positions of said shaft and locking means, said securing means comprising a springpressed plunger mounted in a hole in said ring to engage a selected one of said flats, there being radial slots in said one end of the shaft, each slot corresponding to and opening into a respective fiat beneath said plunger, whereby a blade may be inserted into the slot beneath said plunger to raise the same and thereafter turn said shaft and move said locking means to a new position of adjustment.

WILLIAM SUMMERBELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date France Jan. 1'7, 1922 Italy Sept. 1, 1932 Number Number 

